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AS21273Swisscom (Schweiz) AG

SwitzerlandRegistryRIPE NCC

As of 10th November 2026, AS21273 (Swisscom (Schweiz) AG), a network registered in Switzerland with RIPE NCC, originates 3 IPv4 prefixes covering 768 addresses and 2 IPv6 prefixes. By IPv4 address space that makes it the 45,659th-largest of the 80,723 networks we see originating IPv4, and the 446th-largest of 746 in Switzerland. It is seen behind 2 upstream networks, most often AS3303 (Swisscom (Schweiz) AG) and AS8220 (COLT). Every one of its announcements has a valid RPKI ROA, and none are RPKI-invalid. 100% of its routes reach at least 90% of full-feed peers.

At a glance

IPv4 prefixes

3

IPv6 prefixes

2

IPv4 addresses

768

IPv6 /64s

131k

Upstream graph

The networks AS21273 is seen behind, one and two hops out, drawn from real AS paths.

AS21273Toward the internet core
Upstream graph for AS21273: 6 neighbouring networks observed beyond it across 2 levels. The same networks are listed in the tables below.AS21273Swisscom (Schweiz…This networkAS3303Swisscom (Schweiz…AS8220COLTAS2914NTT America, Inc.AS25091IP-Max SAAS1299Arelion (fka. Tel…AS3356Lumen (Level 3)

Networks observed one and two hops upstream of AS21273 in real AS paths. A thicker line means more vantage points saw that adjacency, so weight tracks how well attested it is — not how much traffic it carries. Adjacency is an observation; whether it is a transit purchase or a settlement-free peering is an inference, and is labelled as one wherever we show it.

Neighbouring networks

4

adjacent networks

Upstreams
250%
Peers
250%
Downstreams
00%

Networks carrying this one's traffic toward the rest of the internet.

Upstreams of AS21273
NetworkCountryRelationshipPathsVantage pts
AS3303Swisscom (Schweiz) AGCHPeer182138
AS8220COLTGBPeer170138

Prefixes

The largest blocks AS21273 originates, widest first.

Largest prefixes originated by AS21273
PrefixAddressesVisibility
193.5.252.0/2425676/76
194.209.118.0/2425676/76
212.243.54.0/2425676/76
2001:918:ff16::/4865.5k × /6462/63
2001:918:ff22::/4865.5k × /6462/63

Routing health

How AS21273's own announcements validate against RPKI and how far they propagate. The same measures for the whole routing table are on the routing table in numbers.

RPKI origin validation

  • Valid100.0%5
  • Invalid0.0%0
  • No ROA0.0%0

Propagation

  • Globally propagated90% of full-feed peers or more100.0%5
  • Partially propagated40% to 90%0.0%0
  • Seen by few peersUnder 40%0.0%0

Prefix sizes

IPv4 — 3 prefixes

IPv6 — 2 prefixes

  • /4865.5k × /64100.0%2

Recent changes

Announcements that started or stopped since 11th Oct 2026.

No announcement by AS21273 started or stopped in this period.

Routing data derived from RouteViews MRT archives, BGPKIT relationship inference and public registry data.